[Gluster-users] Gluster performance

[Whit Blauvelt]

What's Apache doing in terms of file writing? Why not have it read from one
domain, and write to another? Then you could have a DocumentRoot for the
domain to be only read from which points to the backing store on each
server, and a DocumentRoot for the domain that's used for writing files
which points to the Gluster mount.

You'd want separate logs in any case, for the separate Apache instances.
Since Apache only writes to files if you set up scripting specifically to do
that, it's trivial to have all your writes go to a separate domain or
subdomain. Just have every GET or POST that can result in a write to a file
go to the domain with a DocumentRoot on the Gluster share, and all your GETs
that just return static content go to the domain whose DocumentRoot is the
backing store. If some of your GETs or POSTs don't write to files, but
change a backing database, put that database in a different area and use its
native mirroring capacity.

Whit

On Tue, Sep 27, 2011 at 09:50:36PM +0100, Lone Wolf wrote:
> Kind of bizzare I have to agree, but as far as I can understand from the docs
> geo-replication is one way, and I need two way because there can be writes on
> both sides, rsync was an option but I would have to cron it and each side at a
> time, and from my understanding could give me problems of files either going
> missing or not being deleted.
> Using the local for read is an option but since the files are being read and
> written by the same application (apache) I see no way to split that.
> What is more weird is that I managed to get it to read just one side for a
> moment, after restarting gluster because of some adjustments, it started
> reading both nodes again, even restoring config backups had no effect.
>  
> On Tue, Sep 27, 2011 at 1:37 PM, Whit Blauvelt <whit at transpect.com> wrote:
> 
>     Okay, what you're doing is a bizarre use of Gluster anyway. (They'd say you
>     should use the "georeplication" instead - at which point a rsync run from
>     cron will get you to about the same place without using Gluster at all.)
>     But
>     you can have local systems read from the backing store without corrupting
>     the Gluster mirroring. Your writes all have to go through the Gluster
>     mounts, but your reads don't.
> 
>     Whit
> 
>     On Tue, Sep 27, 2011 at 01:22:24PM +0100, Lone Wolf wrote:
>     > Just checked it is mounted with noatime
>     >
>     > No dia 27 de Set de 2011 12:56, "Whit Blauvelt" <
>     whit.gluster at transpect.com>
>     > escreveu:
>     > > On Tue, Sep 27, 2011 at 12:15:50PM +0100, Lone Wolf wrote:
>     > >
>     > >> So I am assuming gluster is distributing the reads, being created with
>     the
>     > >> CLI I tried to edit the configurations manually and added "option
>     > >> read-subvolume volume_name" to the cluster/replicate volume, being the
>     > >> read-subvolume the local one.
>     > >
>     > > Do you have your filesystems mounted "noatime"? If not, every read
>     requires
>     > > the atime (last access time) to be written to the files on both
>     mirrors.
>     > >
>     > > Whit
>     >
> 
>